Overview
Definition:
Inflammatory Bowel Disease (IBD), encompassing Crohn's disease and ulcerative colitis, is a chronic inflammatory condition of the gastrointestinal tract
Pediatric IBD is characterized by its early onset and distinct clinical patterns compared to adult disease
Biologic therapies, such as anti-TNF agents, are increasingly used in managing moderate to severe pediatric IBD, but they significantly increase the risk of opportunistic infections due to immunosuppression
Therefore, a comprehensive pre-biologic vaccination strategy is critical to protect these vulnerable patients.
Epidemiology:
The incidence of pediatric IBD has been rising globally, including in India
While exact figures vary, it is a significant cause of chronic morbidity in children
Biologics are now a cornerstone of treatment for a substantial proportion of these patients, necessitating a proactive approach to infection prevention.
Clinical Significance:
Failure to optimize vaccine status prior to initiating immunosuppressive biologic therapy can lead to severe, potentially life-threatening infections
This proactive vaccination approach is a key component of safe and effective IBD management in pediatrics, directly impacting patient outcomes and reducing healthcare burdens associated with preventable infections
It is a high-yield topic for DNB and NEET SS examinations.
Vaccination Principles
Rationale:
Biologic agents used in IBD therapy, particularly TNF inhibitors, suppress the immune system, increasing susceptibility to vaccine-preventable diseases
Live attenuated vaccines are generally contraindicated in patients on immunosuppressive therapy
Killed vaccines may have reduced efficacy in immunocompromised individuals
Therefore, a thorough pre-treatment assessment and timely administration of necessary vaccines are paramount.
Timing Considerations:
Vaccination ideally should be completed at least 4-6 weeks before initiating biologic therapy to allow for adequate immune response
If immediate initiation of biologics is required, the risk-benefit assessment for live vaccines must be carefully considered
Post-biologic vaccination strategies also need to be defined, especially for inactivated vaccines.
Live Vs Inactivated Vaccines:
Live attenuated vaccines (e.g., MMR, varicella, rotavirus, oral polio, BCG) are generally contraindicated in patients receiving immunosuppressive therapy
Inactivated vaccines (e.g., influenza, pneumococcal, meningococcal, hepatitis B) can be administered but may elicit a suboptimal immune response
The decision to administer live vaccines post-biologics requires careful consideration of the degree of immunosuppression and potential risks.
Pre Biologic Vaccination Checklist
Influenza Vaccine:
Annual inactivated influenza vaccine
Recommended for all children with IBD, especially before and during biologic therapy
Ideally administered prior to starting biologics
Can be given as a trivalent or quadrivalent inactivated influenza vaccine.
Pneumococcal Vaccine:
PCV13 followed by PPSV23 (at age 2-18 years if indicated, spaced at least 8 weeks apart)
For patients 2 years and older who have not received PCV13, administer PCV13 followed by PPSV23 at least 8 weeks later
If already vaccinated with PCV13, revaccination with PPSV23 may be considered 5 years after the first dose of PPSV23 (for those aged 6 years and older).
Meningococcal Vaccine:
MenACWY (conjugate vaccine) and MenB (recombinant vaccine)
Series should be completed before starting biologics
For MenACWY: Typically 2 doses at age 11-12 years and a booster at age 16
If starting before age 11, a different schedule applies
For MenB: A series of 2 or 3 doses depending on the product, followed by a booster if needed.
Hepatitis B Vaccine:
Series of 3 doses
Crucial for all children, especially those with IBD who might be at increased risk or require future medical interventions
Ensure adequate antibody titers post-vaccination if possible.
Human Papillomavirus Vaccine:
HPV vaccine series (2 or 3 doses depending on age at initiation)
Recommended for all adolescents, including those with IBD
Protects against HPV-related cancers
Can be given before or during biologic therapy.
Varicella Vaccine:
Two doses of live attenuated varicella vaccine
Administer at least 4 weeks before starting biologics
If IBD is diagnosed and biologics are imminent, and the child is not immune, administer the vaccine and delay biologics if feasible, or consider varicella-zoster immune globulin (VZIG) if exposure occurs during immunosuppression.
Measles Mumps Rubella Vaccine:
Two doses of live attenuated MMR vaccine
Administer at least 4 weeks before starting biologics
Similar considerations as varicella vaccine regarding delay of biologics or post-exposure prophylaxis.
Rotavirus Vaccine:
Live attenuated rotavirus vaccine series
Recommended for all infants
If a child with IBD is diagnosed before completing the series, continue if feasible before starting biologics
If already on biologics, consult guidelines for administration in immunocompromised infants.
Bcg Vaccine:
Live attenuated BCG vaccine
Generally contraindicated in immunosuppressed patients
If BCG is indicated, it should be given well before starting biologics
Avoid BCG in patients on biologics and during treatment for active tuberculosis.
Assessment And Timing
Medical History:
Thorough review of previous vaccination history
Assess for any contraindications or allergies to vaccine components
Document past varicella infection or immunity status.
Immunological Assessment:
Consider serological testing for immunity to varicella, measles, mumps, and rubella if there is uncertainty about vaccination status or previous infection
Hepatitis B surface antibody titers can assess vaccine response.
Scheduling Strategy:
Prioritize vaccines according to risk and timing of biologic initiation
Live vaccines should be given at least 4 weeks before starting biologics
Inactivated vaccines can be given closer to initiation but ideally completed well in advance
Review the national immunization schedule and adapt it for the IBD patient.
Catch Up Vaccinations:
Develop a personalized catch-up vaccination schedule for any missed vaccines
This often involves a combination of live and inactivated vaccines, requiring careful timing relative to biologic initiation and discontinuation.
Specific Considerations For Biologics
Anti Tnf Agents:
High risk of reactivation of latent tuberculosis (TB) and other infections
BCG vaccine is contraindicated
Ensure TB screening and appropriate prophylaxis before starting anti-TNF agents
Live vaccines are generally avoided.
Other Biologics:
Different biologics (e.g., anti-integrins, JAK inhibitors) may have varying immunosuppressive profiles and specific vaccine recommendations
Always refer to the latest prescribing information and guidelines for the specific biologic agent.
Discontinuation And Reinitiation:
After discontinuation of biologics, the immune system may take several months to recover
The timing for reinitiating live vaccines should be discussed with the treating physician, often after a period of no immunosuppression or with reduced intensity of therapy.
Key Points
Exam Focus:
The critical window for pre-biologic vaccination is 4-6 weeks prior to therapy initiation
Live vaccines are generally contraindicated with immunosuppression
Annual influenza and pneumococcal vaccinations are essential
DNB/NEET SS will test knowledge on specific vaccine contraindications and optimal timing.
Clinical Pearls:
Always create a personalized vaccination plan for each child with IBD
Maintain excellent communication with the family about the importance and schedule of vaccinations
Re-evaluate vaccine status annually
Document all vaccinations meticulously in the patient's chart and encourage parents to maintain records.
Common Mistakes:
Delaying vaccination until after biologic initiation
Administering live vaccines to immunocompromised patients
Not screening for latent infections (e.g., TB) before vaccination or biologic therapy
Inadequate follow-up on vaccine series completion
Overlooking the importance of annual influenza vaccination.